1. Field of the Invention
This invention relates to a device incorporated in an internal combustion engine of a vehicle for positioning an injector having a plurality of nozzle holes.
2. Description of the Related Art
A multi-valve arrangement is now put into practice in an internal combustion engine for a vehicle for the purpose of improving the operation performance of the engine, and also a gasaline injection method of directly injecting fuel by an injector is now widely employed in such an engine for the purpose of preventing environmental pollution and improving the fuel consumption.
When the direct gasaline injection method described above is applied to the multi-valve engine described above so that one injector injects fuel into a plurality of associated intake valves disposed in a fuel system of the engine, it is necessary to inject the fuel toward and into the individual intake valves uniformly or at a predetermined rate. Because of the above requirement, it is a common practice that the injector is provided with fuel nozzle holes in a number equal to the number of the intake valves so that the fuel can be injected from the nozzle holes toward and into the corresponding intake valves.
An example of such a concept is schematically shown in FIG.6. It will be seen in FIG.6 that an injection 3 having three nozzle holes 3a, 3b and 3c injects fuel toward and into a combustion chamber 2 having three intake valves 1a, 1b and 1c. In FIG.6, the reference numerals 4a, 4b and 4c designate intake ports communicating with the respective intake valves 1a, 1b and 1c, and 5 designates an intake manifold.
In such a fuel system, the individual nozzle holes 3a, 3b and 3c of the injector 3 are required to be accurately directed toward the respective intake ports 4a, 4b and 4c. Therefore, various devices for accurately positioning the injector 3 in its circumferential direction have been proposed hitherto. For example, JP-U-60-84767, JP-U-60-137168, JP-U-60-173674, JP-U-60-173675, JP-U-61-41864, JP-U-61-86569 and JP-U-61-88061 disclose such devices.
However, the devices disclosed in those publications have had such various problems that rubber packings tend to be distorted during assembling, the injector itself requires a special structure, the injector itself requires special mechanical processing, and the devices themselves become complex in structure.